"Think about your car, how often does the electric fan kick in the winter?" when not moving, it comes on ALL THE TIME! if it did not the engine would overheat... regardless of outside temp
if your thermostat does not open than you have a problem. either the wrong or bad thermostat.
the thermostat is there to keep the motor at a constant temp, below that temp the motor is running "cold" and not optimum.
the advantage of a liquid coolder motor is it runs at the same temperature if it is cold or warm outside. It is why they ;ast longer and can produce WAY more power than their air cooled counterparts...
(some guys never could understand why a snowmobile motor needed to be water cooled

)
it may take a minute or two longer to open the thermostat on a cold day but not luch longer...
MOTORS GET HOT!
Ask the guys here with x7s with a heater core, they get so hot it can blow them right out of the cab and that is WITH their cooling fan operating! and a larger cooling system than the normal x7... (larger meaning the extra hoses, core and fluid)
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